How physical AI works: The sense-plan-act loop
Physical AI functions through a continuous cycle of sensing, decision-making, and physical action. This "sense-plan-act" loop allows the machine to perceive its surroundings and respond to changes in real-time.
The physical AI process involves four primary stages:
- Data collection and training
- Environmental sensing and sensor fusion
- Decision-making and reinforcement learning
- Physical action and edge computing
Data collection and training
Before deployment, these systems are trained using two complementary inputs: Large datasets of real-world sensor logs and telemetry teach the model what typical conditions look like. Simultaneously, simulated environments built from digital twins allow the model to run through millions of scenarios, safely developing reliable responses before any hardware is exposed to the risks of the physical world.
Environmental sensing and sensor fusion
The system collects data from its surroundings using a variety of sensors, including cameras for visual detail, Lidar for depth, and Radar for motion detection. To create a high-confidence "ground truth," the system uses sensor fusion to combine these disparate inputs. This allows the AI to resolve conflicting data, such as distinguishing between a solid object and a shadow, to maintain an accurate view of the environment.
Decision-making and reinforcement learning
The system processes sensor data using perception models to interpret the environment and policy models to select a response.
Many physical AI systems utilize reinforcement learning, where the model improves by attempting actions and receiving feedback. For example, a robotic arm learning to grip irregular objects refines its approach across repeated attempts as actions that lead to better outcomes are reinforced.
Physical action and edge computing
Once a decision is made, the system acts through mechanical components like motors, conveyors, or robotic arms. To achieve the millisecond response times required for safety, physical AI relies on edge computing. By processing data on the machine itself or a local gateway, the system avoids the latency of a round-trip to a distant cloud, ensuring the machine can react instantly to environmental changes.